Please activate JavaScript!
Please install Adobe Flash Player, click here for download
ePaper created 2017-11-25, 21:52:13 | version 1.38.0
6 exhibitors Greater New York Dental Meeting — Nov. 26, 2017 New generation of CAD/CAM materials represents synergy of ceramics and composites HC Block/Disk designed to minimize flaws attributed to esthetic and high-strength ceramics By Shofu Dental Staff n Until recently, a clinician’s deci- sion was quite straightforward when selecting CAD/CAM restorations, as typically, tougher materials were associated with poor esthetics and excellent esthetics were associated with low strength. Today, CAD/CAM crowns, bridges, inlays/onlays and veneers can be cre- ated with a multitude of materials, including ceramics (esthetic ceram- ics, high-strength ceramics, hybrid ceramics and zirconia), CAD/CAM composites, fiber-reinforced resins, polymers and metals. Ceramics are by far the most com- mon materials used to fabricate CAD/ CAM restorations. In the pioneering years of CAD/CAM technology, feld- spathic porcelain was the restorative material of choice for many clini- cians as this material best matched the desired physical properties — excellent translucency and moderate strength. While esthetic, porcelain is brittle with a low fracture toughness and a high proneness to failure in the pres- ence of flaws. leucite-reinforced To overcome this problem. new materials with greater strength were pursued. First, then lithium-disilicate glass ceramics, both of which demonstrate higher flexural strength than porcelain. Tough and esthetic, when these mate- rials are adequately prepped, han- dled and bonded they demonstrate a good success rate. However, when the margins are thin, a bond to the underlying tooth is deficient or an adjustment is needed, the failure rate of restorations with high-strength ceramics tends to dra- matically increase. In response to the limitations of high-strength ceramics, new poly- mer-based resin-composite materials such as HC Block/Disk (Shofu) have been developed. This new category of materials, referred to as CAD/CAM composites and/or hybrid ceramics, represents the synergy of ceramics and composites with their respective beneficial mechanical properties. Intended to provide clinicians 5 Full-contour HC Block/Disk crown (Shofu) with a short implant (Bicon). Restoration was characterized with Lite Art Stains (Shofu). (Photo/Courtesy of Muneki Hirayama, DMD, Boston, Mass.) with the capability of restoring teeth in one appointment, HC Block/Disk represents a generation of new CAD/ CAM composites, according to Shofu, the company behind the product. It features a unique nanostructure, polymerization mode, matrix compo- sition, augmented filler content and a highly homogenous formulation designed to minimize flaws attrib- uted to esthetic and high-strength ceramics. Composed of 61-percent zirco- nium silicate embedded in a high- temperature/high-pressure polymer matrix, a densely packed nanofiller of HC Block/Disk forms a skeleton that uniformly absorbs masticatory forces and promotes resistance to breakdown phenomena. When compared to other CAD/ CAM materials, HC Block/Disk mani- fests better machinability in terms of milling time, damage tolerance, Here in New York To learn more about the HC Block/Disk, stop by the Shofu booth, No. 4408. wear of CAD/CAM instruments and the ability to be milled in a very low thickness, according to the com- pany. The high flexural strength of 191 MPa and Vickers hardness of 66 Hv0.2 make HC Block/Disk a good candidate for posterior restorations, implant-supported cases and long- term provisionals. Additionally, the hardness of the material also demonstrates values closer to dentin (ca. 65 Hv0.2), and thus no excessive antagonist wear can be observed, which is a concern when using conventional ceramics. Repairs of porcelain, zirconia and ‘When compared to other CAD/CAM materials, HC Block/Disk manifests better machinability in terms of milling time, damage tolerance, wear of CAD/CAM instruments and the ability to be milled in a very low thickness’ other ceramic materials have proven to be challenging. However, with HC Block/Disk, restorations can suc- cessfully be adjusted chairside with either a direct resin composite such as Beautifil Flow Plus (Shofu) or an indirect composite such as Ceramage (Shofu).